This research uses a previously successfully tested research design that makes use of a true experimental technique to examine how structure and presenting conditions affect dentists' treatment plans. It uses four actors with actual dental disease who will be randomly assigned and sent to be examined by 210 general practice dentists in Metropolitan Chicago, who have been randomly selected and assigned to five separate groups. The independent variables to be tested are the methods patients use to pay for treatment (fee-for-service [ffs], prepaid capitation [IPA], or Preferred Provider Organization ([PPO]); the specialty of the dentist (oral surgeon or general practitioner); the type of pathology presented by the patient (numerous dental caries, moderate periodontal disease, temporomandibular joint disorder, or asymptomatic, unerupted and impacted third molars [wisdom teeth]); and whether the dentist is in a solo or a group practice. Because IPA and PPO dentists routinely also see patients on a ffs basis, they will be further divided into two sub-groups to determine if these dentists plan treatment for their ffs patients differently from how they plan treatment for their IPA or PPO patients. The actors will bring their own recently taken radiographs to each dentist for the examination. After each dentists examines the patient and plans treatment for him/her (no treatment will be performed), the actor will ask for the radiographs to seek a second opinion, leave the dentist's office and record on a specially prepared chart the treatment suggested by each dentist. Each treatment procedure will be converted into a dollar value using a single fee schedule. Thus the dollar will act as a proxy for the amount and type (because of the difference in the cost of each procedure) of treatment recommended by the dentists. An investigator will then conduct a face-to-face interview with the dentists to determine how dentists decide upon treatment and which characteristics of their patients are important in making their decisions. The dentists will then be told about the research and that they had been uninformed subjects in an experiment. After a full review, the University IRB approved the study protocol.